For an angle Θ with the point (12, −5) on its terminating side, what is the value of cosine?

Question

anonymous · Answer

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anonymous · Answer

ok then what? sorry I just taught myself literally 15 minutes ago

anonymous · Answer

I know how to set it up but I dontknow what to do next

anonymous · Answer

$$Cos(\theta) =\frac{ Adjacent }{ Hypotenuse }$$

The terminal side is the hypotenuse.
$$Hypotenuse = \sqrt{A^2+B^2}$$
$$Hypotenuse = \sqrt{(12)^2+(-5)^2}$$

Solve for the Hypotenuse and then use the Adjacent side, the side adjacent to your angle, which is 12 in your case.

anonymous · Answer

You should be able to solve from here.

anonymous · Answer

so √144+25
√169
13? but that's not an option

anonymous · Answer

That is only your hypotenuse. You must find the value of cosine by relating it to your formula for cos(angle)

anonymous · Answer

ohhh so then what?

anonymous · Answer

Relate it to your cosine(angle) formula. Adjacent side over Hypotenuse.

anonymous · Answer

how do I find adj?

anonymous · Answer

It is given.

anonymous · Answer

oh so 12/13?

anonymous · Answer

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